The present invention relates to vibration damping devices of elastic material, and more particularly to the use of such devices in chain saws thereby reducing the vibrations from the engine and the guide bar during operation.
In general, a chain saw comprises two primary components; a body and a handle. The body includes a motor having a crankcase, a guide bar attachment, an endless cutter chain, and means for rotating the endless cutter chain about the guide bar attachment. The handle includes a manual gripping portion, a frame portion, and often times a fuel tank and an oil tank. The body and the handle are interconnected so they can move independent from one another.
It is know in the art to arrange vibration dampers of rubber or steel springs in the body or the handle of the chain saw by either fastening them with screws of pressing them into seats formed in the saw. When designing such damping devices there is a problem with balancing between stiff and soft elements so that the damping of the vibrations becomes efficient while at the same time obtaining sufficient stiffness between the handle and the body for guiding the saw during operation. Under extreme conditions, such as sawing very dense wood or using an abnormally long guide bar, it is desired to otain a very progressive spring characteristic when large deflections occur in the damping arrangement. In order to obtain such a progressive characteristic special fastening arrangements and a reinforcement of the element with a stiffening means are required whose influence on the elasticity of the element does not take place until a certain deflection has occurred.